Texas Instruments TMS320F28004 Series, Руководство пользователя

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Advisory ADC: Interrupts may Stop if INTxCONT (Continue-to-Interrupt Mode) is not Set
Revisions Affected 0, A, B
Details If ADCINTSELxNx[INTxCONT] = 0, then interrupts will stop when the ADCINTFLG is set
and no additional ADC interrupts will occur.
When an ADC interrupt occurs simultaneously with a software write of the
ADCINTFLGCLR register, the ADCINTFLG will unexpectedly remain set, blocking future
ADC interrupts.
Workarounds 1. Use Continue-to-Interrupt Mode to prevent the ADCINTFLG from blocking additional
ADC interrupts:
ADCINTSEL1N2[INT1CONT] = 1;
ADCINTSEL1N2[INT2CONT] = 1;
ADCINTSEL3N4[INT3CONT] = 1;
ADCINTSEL3N4[INT4CONT] = 1;
2. Ensure there is always sufficient time to service the ADC ISR and clear the
ADCINTFLG before the next ADC interrupt occurs to avoid this condition.
3. Check for an overflow condition in the ISR when clearing the ADCINTFLG.
Check ADCINTOVF immediately after writing to ADCINTFLGCLR; if it is set, then
write ADCINTFLGCLR a second time to ensure the ADCINTFLG is cleared. The
ADCINTOVF register will be set, indicating an ADC conversion interrupt was lost.
AdcaRegs.ADCINTFLGCLR.bit.ADCINT1 = 1; //clear INT1 flag
if(1 == AdcaRegs.ADCINTOVF.bit.ADCINT1) //ADCINT overflow
{
AdcaRegs.ADCINTFLGCLR.bit.ADCINT1 = 1; //clear INT1 again
// If the ADCINTOVF condition will be ignored by the application
// then clear the flag here by writing 1 to ADCINTOVFCLR.
// If there is a ADCINTOVF handling routine, then either insert
// that code and clear the ADCINTOVF flag here or do not clear
// the ADCINTOVF here so the external routine will detect the
// condition.
// AdcaRegs.ADCINTOVFCLR.bit.ADCINT1 = 1; // clear OVF
}
www.ti.com Silicon Revision B Usage Notes and Advisories
SPRZ439G – JANUARY 2017 – REVISED AUGUST 2022
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TMS320F28004x Real-Time MCUs Silicon Errata
Silicon Revisions B, A, 0
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